Document possible values of schema fields (#455)

* Document possible values of schema fields

* Change from possible to supported

stackit/internal/utils/utils.go

@@ -76,3 +76,17 @@ func SimplifyBackupSchedule(schedule string) string {
 	})
 	return simplifiedSchedule
 }
+
+func SupportedValuesDocumentation(values []string) string {
+	if len(values) == 0 {
+		return ""
+	}
+	return "Supported values are: " + strings.Join(quoteValues(values), ", ") + "."
+}
+
+func quoteValues(values []string) []string {
+	for i, value := range values {
+		values[i] = fmt.Sprintf("`%s`", value)
+	}
+	return values
+}